Yerba mate(ilex paraguariensis(IP))is a plant widely consumed in South America as a hot(mate)or cold infusion beverage(tereré). During the last years, there was an increasing interest in its health properties supported by a growing scientific evidence. These studies showed that the IP could have hepatoprotective, hypocholesterolemic, diuretic and antioxidant properties. Furthermore it showed to be a nervous system stimulant and protectant(1). Recently, there were reports about its invitro potential to inhibit the Monoaminooxidase(MAO) which can have effects on mood state(2).

Exploratory research to study possible associations between the use of IP and mood symptoms.

An observational cross-sectional study was conducted by an online survey in paraguayan population through an invitation. The survey collected data information about sociodemographics conditions, substance use(including IP), Spielberg's State-Trait Anxiety Inventory and PHQ-9 scale for depressive symptoms. A descriptive and multiple lineal regression analysis of the data was performed.

300 subjects accepted the invitation and information was obtained of about 76% of them. The sample mean age(SD) was 27(7,4), most of them females(61,6%)and with universitary studies(66,1%). The 86% of the sample consumed IP regularly and 56% daily. Only a 3,5% reported previous psychiatric history. A significant relationship was observed between the use of IP and daily alcohol(p=0,022). No relevant associations were found concerning IP use and anxiety trait-state or depressive symptoms after adjusting for the use of coffee, tea, alcohol and others sociodemographic variables.

No significant associations were found in the sample studied between the use of IP and state-trait anxiety or depressive symptoms. Although, given the frequency of its use, the association with alcohol consumption and its potential clinical applications, more and bigger studies might be necessary.